implement ability to pipe in text (#3)

build.zig

@@ -66,9 +66,13 @@ pub fn build(b: *std.build.Builder) !void {
         .target = target,
         .optimize = optimize,
     });
+    exe_tests.linkLibrary(im_dep.artifact("MagickWand"));
+    exe_tests.linkLibrary(z_dep.artifact("z"));
+    exe_tests.linkLibrary(i2cdriver);
+    exe_tests.addIncludePath("lib/i2cdriver");
 
     const test_step = b.step("test", "Run unit tests");
-    test_step.dependOn(&exe_tests.step);
+    test_step.dependOn(&exe_tests.run().step);
 }
 
 // Should be able to remove this

src/main.zig

@@ -24,7 +24,7 @@ const LINES = 8;
 // Device specifications
 const PAGES = 8;
 
-var lines: [LINES]*const [:0]u8 = undefined;
+var lines: [LINES]*[:0]u8 = undefined;
 
 fn usage(args: [][]u8) !void {
     const writer = std.io.getStdErr().writer();
@@ -33,40 +33,85 @@ fn usage(args: [][]u8) !void {
     try writer.print("\te.g. \"-1 'hello world'\" will display \"hello world\" on line 1\n", .{});
     std.os.exit(1);
 }
+const Options = struct {
+    background_filename: [:0]u8,
+    device_file: [:0]u8,
+};
 pub fn main() !void {
     const alloc = std.heap.c_allocator;
     //defer alloc.deinit();
     const args = try std.process.argsAlloc(alloc);
     defer std.process.argsFree(alloc, args);
-    if (args.len < 2) try usage(args);
-    const prefix = "/dev/ttyUSB";
-    const device = try alloc.dupeZ(u8, args[1]);
-    defer alloc.free(device);
-    if (!std.mem.eql(u8, device, "-") and !std.mem.startsWith(u8, device, prefix)) try usage(args);
 
-    // stdout is for the actual output of your application, for example if you
-    // are implementing gzip, then only the compressed bytes should be sent to
-    // stdout, not any debugging messages.
     const stdout_file = std.io.getStdOut().writer();
     var bw = std.io.bufferedWriter(stdout_file);
     const stdout = bw.writer();
     defer bw.flush() catch unreachable; // don't forget to flush!
 
-    var filename: [:0]u8 = @constCast("");
-    var b: [1]u8 = undefined;
-    const nothing: [:0]u8 = try std.fmt.bufPrintZ(&b, "", .{});
+    // If we have stdin redirected, we want to process that before
+    // we take command line options. So cli will overwrite any lines specified
+    // from the file
+    const stdin_file = std.io.getStdIn();
+    var stdin_data: [WIDTH * HEIGHT + 1]u8 = undefined;
+    // Need this to support deallocation of memory
+    var line_inx: usize = 0;
+    var stdin_lines: [LINES][:0]u8 = undefined;
+    defer {
+        for (0..line_inx) |i| {
+            alloc.free(stdin_lines[i]);
+        }
+    }
+    var nothing: [:0]u8 = @constCast("");
     for (lines, 0..) |_, i| {
         lines[i] = &nothing;
     }
+    if (!stdin_file.isTty()) {
+        const read = try stdin_file.readAll(&stdin_data);
+        if (read == stdin_data.len) {
+            try std.io.getStdErr().writer().print("ERROR: data provided exceeds what can be sent to device!\n", .{});
+            try usage(args);
+        }
+        var read_data = stdin_data[0..read];
+        var it = std.mem.split(u8, read_data, "\n");
+        while (it.next()) |line| {
+            if (line.len == 0) continue;
+            stdin_lines[line_inx] = try alloc.dupeZ(u8, line);
+            lines[line_inx] = &stdin_lines[line_inx];
+            line_inx += 1;
+        }
+    }
+    std.debug.print("delme: {s}\n", .{lines[0].*});
+    const opts = try processArgs(alloc, args, &lines);
+    defer alloc.destroy(opts);
+    if (opts.background_filename.len > 0) try stdout.print("Converting {s}\n", .{opts.background_filename});
+    var pixels: [WIDTH * HEIGHT]u8 = undefined;
+    try convertImage(opts.background_filename, &pixels, textForLine);
+    try bw.flush();
+
+    // We should take the linux device file here, then inspect for ttyUSB vs
+    // i2c whatever and do the right thing from there...
+    try sendPixels(&pixels, opts.device_file, 0x3c);
+
+    // try stdout.print("Run `zig build test` to run the tests.\n", .{});
+}
+
+fn processArgs(allocator: std.mem.Allocator, args: [][:0]u8, line_array: *[LINES]*const [:0]u8) !*Options {
+    if (args.len < 2) try usage(args);
+    const prefix = "/dev/ttyUSB";
+    var opts = try allocator.create(Options);
+    opts.device_file = args[1];
+    if (!std.mem.eql(u8, opts.device_file, "-") and !std.mem.startsWith(u8, opts.device_file, prefix)) try usage(args);
+
+    opts.background_filename = @constCast("");
     var is_filename = false;
     var line_number: ?usize = null;
-    for (args, 0..) |arg, i| {
+    for (args[1..], 1..) |arg, i| {
         if (std.mem.eql(u8, "-bg", arg)) {
             is_filename = true;
             continue;
         }
         if (is_filename) {
-            filename = args[i]; // arg capture changes value...
+            opts.background_filename = args[i]; // arg capture changes value...
             break;
         }
         if ((arg[0] == '-' and arg.len > 1) and areDigits(arg[1..])) {
@@ -81,30 +126,13 @@ pub fn main() !void {
                 );
                 std.os.exit(1);
             }
-            std.debug.print("line {d} text: \"{s}\"\n", .{ line, arg });
-            lines[line] = &args[i];
+            std.log.debug("line {d} text: \"{s}\"\n", .{ line, arg });
+            line_array.*[line] = &args[i];
             line_number = null;
             continue;
         }
     }
-
-    if (filename.len > 0) try stdout.print("Converting {s}\n", .{filename});
-    var pixels: [WIDTH * HEIGHT]u8 = undefined;
-    try convertImage(alloc, filename, &pixels, textForLine);
-    try stdout.print("Sending pixels to display\n", .{});
-    // var i: usize = 0;
-    // while (i < HEIGHT) {
-    //     try stdout.print("{d:0>2}: {s}\n", .{ i, fmtSliceGreyscaleImage(pixels[(i * WIDTH)..((i + 1) * WIDTH)]) });
-    //     // try stdout.print("{d:0>2}: {s}\n", .{ i, std.fmt.fmtSliceHexLower(pixels[(i * WIDTH)..((i + 1) * WIDTH)]) });
-    //     i += 1;
-    // }
-
-    // We should take the linux device file here, then inspect for ttyUSB vs
-    // i2c whatever and do the right thing from there...
-    try sendPixels(&pixels, device, 0x3c);
-    try stdout.print("done\n", .{});
-
-    // try stdout.print("Run `zig build test` to run the tests.\n", .{});
+    return opts;
 }
 
 fn areDigits(bytes: []u8) bool {
@@ -167,6 +195,7 @@ fn sendPixelsThroughI2CDriver(pixels: []const u8, file: [*:0]const u8, device_id
     defer bw.flush() catch unreachable; // don't forget to flush!
     try stdout.print("Connecting to I2CDriver on {s}. If progress stalls, unplug device and re-insert.\n", .{c_file});
     try bw.flush();
+    try stdout.print("Sending pixels to display...", .{});
     c.i2c_connect(&i2c, c_file);
     try stdout.print("Device connected\n", .{});
     if (i2c.connected != 1) return error.I2CConnectionFailed;
@@ -189,9 +218,11 @@ fn sendPixelsThroughI2CDriver(pixels: []const u8, file: [*:0]const u8, device_id
 
     // Write data to device
     try i2cWrite(&i2c, &pixels_write_command);
-    for (0..HEIGHT) |i| {
-        std.debug.print("{d:0>2}: {s}\n", .{ i, fmtSliceGreyscaleImage(pixels[(i * WIDTH)..((i + 1) * WIDTH)]) });
-    }
+    // Leaving this here because we'll need it later I think
+    // for (0..HEIGHT) |i| {
+    //     std.log.debug("{d:0>2}: {s}\n", .{ i, fmtSliceGreyscaleImage(pixels[(i * WIDTH)..((i + 1) * WIDTH)]) });
+    // }
+    try stdout.print("done\n", .{});
 }
 
 fn packPixelsToDeviceFormat(pixels: []const u8, packed_pixels: []u8) void {
@@ -274,8 +305,7 @@ fn reportMagickError(mw: ?*c.MagickWand) !void {
 fn textForLine(line: usize) []u8 {
     return lines[line].*;
 }
-fn convertImage(alloc: std.mem.Allocator, filename: [:0]u8, pixels: *[WIDTH * HEIGHT]u8, text_fn: *const fn (usize) []u8) !void {
-    _ = alloc;
+fn convertImage(filename: [:0]u8, pixels: *[WIDTH * HEIGHT]u8, text_fn: *const fn (usize) []u8) !void {
     c.MagickWandGenesis();
     defer c.MagickWandTerminus();
     var mw = c.NewMagickWand();
@@ -309,13 +339,13 @@ fn convertImage(alloc: std.mem.Allocator, filename: [:0]u8, pixels: *[WIDTH * HE
     const w = c.MagickGetImageWidth(mw);
     const h = c.MagickGetImageHeight(mw);
 
-    std.debug.print("Original dimensions: {d}x{d}\n", .{ w, h });
+    std.log.debug("Original dimensions: {d}x{d}\n", .{ w, h });
     // This should be 48x64 with our test
     // Command line resize works differently than this. Here we need to find
     // new width and height based on the input aspect ratio ourselves
     const resize_dimensions = getNewDimensions(w, h, WIDTH, HEIGHT);
 
-    std.debug.print("Dimensions for resize: {d}x{d}\n", .{ resize_dimensions.width, resize_dimensions.height });
+    std.log.debug("Dimensions for resize: {d}x{d}\n", .{ resize_dimensions.width, resize_dimensions.height });
 
     status = c.MagickResizeImage(mw, resize_dimensions.width, resize_dimensions.height, c.UndefinedFilter);
     if (status == c.MagickFalse)
@@ -362,7 +392,6 @@ fn convertImage(alloc: std.mem.Allocator, filename: [:0]u8, pixels: *[WIDTH * HE
             }
             break;
         }
-        std.debug.print("left_spaces: {d}. Text: \"{s}\"\n", .{ left_spaces, text });
         x += (FONT_WIDTH * left_spaces);
         mw = try drawString(mw, text[@intCast(usize, left_spaces)..], x, y);
     }
@@ -488,23 +517,38 @@ fn getNewDimensions(width: usize, height: usize, desired_width: usize, desired_h
     };
 }
 
-fn logo() !void {
-    c.MagickWandGenesis();
+test "gets correct bytes" {
+    const bg_file: [:0]u8 = @constCast("logo:");
+    const opts = .{ .background_filename = bg_file, .device_file = "-" };
+    const empty: [:0]u8 = @constCast("");
+    for (&lines) |*line| {
+        line.* = &empty;
+    }
+    const line: [:0]u8 = @constCast("Hello\\!");
+    lines[5] = &line;
+    var pixels: [WIDTH * HEIGHT]u8 = undefined;
 
-    // Create a wand
-    var mw = c.NewMagickWand();
+    var expected_pixels: *const [WIDTH * HEIGHT]u8 = @embedFile("testExpectedBytes.bin");
 
-    // Read the input image
-    _ = c.MagickReadImage(mw, "logo:"); // TODO: What is the return val?
-    // write it
-    _ = c.MagickWriteImage(mw, "logo.jpg"); // TODO: What is the return val?
-
-    // Tidy up
-    if (mw) |w| mw = c.DestroyMagickWand(w);
-
-    c.MagickWandTerminus();
+    // [_]u8{..,..,..}
+    try convertImage(opts.background_filename, &pixels, textForLine);
+    // try writeBytesToFile("testExpectedBytes.bin", &pixels);
+    try std.testing.expectEqualSlices(u8, expected_pixels, &pixels);
+}
+fn writeBytesToFile(filename: []const u8, bytes: []u8) !void {
+    const file = try std.fs.cwd().createFile(filename, .{
+        .read = false,
+        .truncate = true,
+        .lock = .Exclusive,
+        .lock_nonblocking = false,
+        .mode = 0o666,
+        .intended_io_mode = .blocking,
+    });
+    defer file.close();
+    const writer = file.writer();
+    try writer.writeAll(bytes);
+    // try writer.print("pub const chars = &[_][]const u8{{\n", .{});
 }
-
 test "simple test" {
     var list = std.ArrayList(i32).init(std.testing.allocator);
     defer list.deinit(); // try commenting this out and see if zig detects the memory leak!